T19 Howitzer Motor Carriage

T19 Howitzer Motor Carriage
A T19 Howitzer Motor Carriage.
Type	Self-propelled gun
Place of origin	United States
Service history
In service	1942–45
Used by	United States
Wars	World War II
Production history
Designer	Ordnance Department
Designed	1941
Manufacturer	Diamond T
Produced	January – April 1942
No. built	324
Specifications
Weight	9.54 short tons (8.65 t)
Length	20 ft 2 in (6.15 m)
Width	6 ft 5 in (1.96 m)
Height	7 ft 8 in (2.34 m)
Crew	6
Armor	Howitzer shield: 0.25 in (6.4 mm) Windshield: 0.50 in (13 mm) Sides and rear: 0.25 in (6.4 mm)
Main armament	M2A1 105 mm Howitzer (8 rounds)
Secondary armament	.50 cal (12.7 mm) M2 Browning machine gun
Engine	White 160AX, 386 in3 (6,330 cc), 6-cylinder, gasoline, compression ratio 6.3:1 147 hp (110 kW)
Power/weight	14.7 hp/ton
Suspension	Front: semi-elliptical longitudinal leaf spring rear: single vertical volute spring bogie
Fuel capacity	60 US gal (230 l)
Operational range	200 mi (320 km)
Speed	45 mph (72 km/h)

The T19 Howitzer Motor Carriage (HMC), was a 105 mm (4.1 in) howitzer mounted on a M3 Half-track chassis. It saw service during World War II with the U.S. Army. Its secondary armament consisted of an air-cooled .50 in (13 mm) M2 machine gun for local defense. It was produced by Diamond T between January 1942 and April 1942.

It principally served in the North African Campaign, although some served in the Allied invasion of Sicily and the subsequent Italian Campaign, and even as late as the invasion of southern France in 1944.

The T19 Howitzer Gun Motor Carriage was similar to the M3 Half-track, as it shared the same chassis, engine, suspension, armor, and fuel tank. It was 20 ft 2 in long, 6 ft 5 in wide, 7 ft 8 in high, with a weight of 9.54 short tons. The suspension consisted of semi-elliptical longitudinal leaf springs for the wheels and vertical volute springs for the tracks. It was powered by a White 160AX, 147 hp, 386 in³, six-cylinder gasoline engine with a compression ratio of 6.3:1. It was capable of a maximum road speed of 45 mph. The power-to-weight ratio was 14.7 hp/ton.

The vehicle was operated by a crew of six. Maximum armor was only 0.5 inch at the windshield and 0.25 inches everywhere else. The armament consisted of one 105 mm M2A1 howitzer (equipped with eight rounds of ammunition) with a single .50 caliber (12.7 mm) M2 Browning machine gun (equipped with 300 rounds of ammunition) for local defense.

In the autumn of 1941, when the Armored Force expanded, an urgent need for self-propelled artillery arose. Although a full-track chassis was preferred, the situation required the use of whatever vehicles were immediately available. The M3 Half-track was selected to carry a 105 mm M2A1 howitzer. Although this design had originally been suggested in September 1941, it had not been taken up. However, the urgency of the requirement resulted in the approval by the Adjutant General and the construction of a prototype was authorized by OCM 17391, dated 31 October 1941; the new vehicle designated as the 105 mm Howitzer Motor Carriage T19.